EP 1197664 A1 20020417 - Pneumatic forcing arrangement
Title (en)
Pneumatic forcing arrangement
Title (de)
Pneumatische Betätigungsvorrichtung
Title (fr)
Dispositif d'actionnement pneumatique
Publication
Application
Priority
GB 0025275 A 20001014
Abstract (en)
A pneumatic forcing arrangement 10 (Fig 1), suitable for actuating an operating rod 101 of a hydraulic braking system 100 under test, effects displacement and applies force to the rod followed by releasing it. Actuation is repeated cyclically, which requires rapid transfer of compressed air to precise demand pressures without hysteresis. A fast response, low flow capacity control valve 40 is controlled to provide a demanded pressure at outlet port 43 and with relay valve means 60, comprising quick release supply and exhaust valves 70 and 80, supplies compressed air to a transducer 20 including a diaphragm coupled to the rod 101. The valves 70 and 80 each respond to a negative pressure between a first port 77, 87 and second port 78, 88 to open and the supply to the port 77 and control valve 40 is by way of restriction means 94 so that in response to a step increase demanded pressure at 43 the control valve input pressure drops and the supply relay valve 70 opens to feed the transducer until the pressure recovers. A drop in control valve outlet pressure vents the transducer through valve 80. Flow means 297 (Fig 2) may be disposed between the supply rely valve and control valve and effect a small delay in opening of the relay valve, and the flow restriction means (294) may comprise separately controllable restrictors to finely tune flows to each of these valves. <IMAGE>
IPC 1-7
IPC 8 full level
B60T 13/40 (2006.01); B60T 15/18 (2006.01); F15B 11/028 (2006.01); F15B 11/042 (2006.01); F15B 19/00 (2006.01)
CPC (source: EP)
B60T 13/40 (2013.01); B60T 15/18 (2013.01); F15B 11/028 (2013.01); F15B 11/042 (2013.01); F15B 19/00 (2013.01); F15B 2211/20538 (2013.01); F15B 2211/40515 (2013.01); F15B 2211/426 (2013.01); F15B 2211/45 (2013.01); F15B 2211/455 (2013.01); F15B 2211/46 (2013.01); F15B 2211/625 (2013.01); F15B 2211/6309 (2013.01); F15B 2211/6313 (2013.01); F15B 2211/6343 (2013.01); F15B 2211/6654 (2013.01); F15B 2211/7052 (2013.01); F15B 2211/76 (2013.01)
Citation (search report)
- [X] US 3259439 A 19660705 - BUELER RICHARD C
- [X] US 4496192 A 19850129 - GRAUEL INGOLF [DE], et al
- [A] WO 9837330 A1 19980827 - KOMATSU MFG CO LTD [JP], et al
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR
DOCDB simple family (publication)
EP 1197664 A1 20020417; GB 0025275 D0 20001129; GB 0123495 D0 20011121; GB 2368616 A 20020508
DOCDB simple family (application)
EP 01308377 A 20011001; GB 0025275 A 20001014; GB 0123495 A 20010929